VALORIZATION OF RESIDUAL LIGNIN FROM PAPERMILLS

VALORIZATION OF RESIDUAL LIGNIN FROM PAPERMILLS

From 1983-01-01
to 1986-01-01

Project details

Total cost:

Not available

EU contribution:

Not available

Coordinated in:

Belgium

Objective

THE WORKING PLAN CONSISTS IN STUDYING AND IMPROVING THE FEASIBILITY OF TWO SPECIFIC VALORIZATIONS OF LIGNOSULPHONATES, VALORIZATIONS THAT ARE MORE ATTRACTIVE THAN A MERE COMBUSTION. IN THE INDUSTRY OF PARTICLE BOARDS, CONCENTRATED LIGNOSULPHONATES - E.G. THOSE OF WHICH THE PERCENTAGE IN DRY SUBSTANCES HAS BEEN INCREASED TO 50% OR POWDERS - CAN PARTLY BE USED AS SUBSTITUTES FOR GLUE (BY 5 TO 15%). THE DIFFERENCE OF COST BETWEEN BOTH PRODUCTS LEADS TO A SAVING, THE TECHNOLOGICAL ADVANTAGE OF WHICH IS NOT OBVIOUS. NOWADAYS THE SUBSTITUTION TAKES PLACE ONLY IN THE CASE OF STANDARD GLUES. THE LIGNOSULPHONATE(CALCIUM, MAGNESIUM, SODIUM) IS CHOSEN ACCORDING TO MANUFACTURING PARAMETERS, RATHER THAN BY TAKING THE TECHNOLOGICAL PROPERTIES OF THE BOARDS INTO ACCOUNT. PREVIOUS STUDIES INDICATE THAT IT IS QUITE POSSIBLE AND EVEN NECESSARY TO IMPROVE THE BEHAVIOUR OF THE LIGNOSULPHONATES INCORPORATED WITH THE THERMO-HARDENING GLUES USED IN THE INDUSTRY OF PARTICLE BOARDS. THE PROJECT AIMS AT MODIFYING THE LIGNOSULPHONATES BY STUDYING THE INFLUENCE OF VARIOUS PARAMETERS OF DEHYDRATION, THE MODIFICATION OF PH, THE INCORPORATION OF ADDITIVES, THE EXTRACTION OF SOME COMPONENTS(DESUGARING...). THE VALORIZATION OF THE SUGARED HYDROLYSATE WILL BE STUDIED AS WELL.

THAT STAGE OF THE RESEARCH WILL BE FOLLOWED BY THE MANUFACTURE - UNDER STANDARD CONDITIONS - OF PARTICLE BOARDS. THE PURPOSE IS TO MAKE CLEAR, BY MEANS OF BOTH PHYSICAL AND CHEMICAL CLASSICAL TRIALS, THE POSSIBLE ADVANTAGES OF MODIFYING LIGNOSULPHONATES.

THE ALKALINE LIGNIN THAT HAVE BEEN ISOLATED FROM THE BLACK LIQUORS BY MEANS OF ACIDIFICATION SHOW PROPERTIES THAT ARE RATHER SIMILAR TO THOSE LIGNOSULPHONATES. HOWEVER THEIR POSSIBILITIES OF VALORIZATION ARE LESS THAN THOSE OF LIGNOSULPHONATES, FOR ALKALINE LIGNINS ARE INSOLUBLE IN WATER.

THE SURVEY WILL ALSO BE CARRIED OUT ON ALKALI-LIGNINS AFTER THEY HAVE BEEN MODIFIED IN ORDER TO BECOME STABLE IN NEUTRAL OR ACID CONDITIONS (EXAMPLE : WESTVACO PROCESS).

THE INTEREST OF THE PROCESS LIES IN THE FACT THAT A RANGE OF LIGNOSULPHONATES HIGHLY VARYING IN SULPHONIC ACID CAN BE OBTAINED THUS LEADING TO SPECIFIC PROPERTIES.

THE PRODUCTION OF VANILLIN IS THE SECOND WAY OF VALORIZING LIGNIN RESIDUES THAT HAS BEEN TAKEN INTO ACCOUNT.

THE OXIDATION OF LIGNIN IN ALKALINE MEDIUM LEADS TO THE DEGRADATION OF THE POLYMER AND TO THE FORMATION OF A LARGE NUMBER OF AROMATIC COMPOUNDS OF THE PHENOLICIC TYPE.